Apparatus for treating ores to sinter them



A. S. DWIGHT.

APPARATUS FOR TREATING ORES T0 SINTER THEM.

APPLICATION FILED MAY 8. I912.

Patented Oct. 24, 1922.

3 SHEETSSHEET l.

w WW A. S. DWIGHT. APPARATUS FOR TREATING ORES T0 SINTER THEM. APPLICATION FILED MAY 3, I912. 1,433,352. Patented Oct-24,1922

3 SHEETSSHEET 2.

VW'TNEHEF.

A. S. DWlGHT.

APPARATUS FOR TREATING ORES T0 SINTER THEM.

APPLICATION FILED MAY 8. I912.

Patented Oct. 24, 1922.

3 SHEETSSHEET 3.

Patented Oct. 24, 1922.

UNITED STATES PATENT OFFICE.

ARTHUR S. DWIGHT, OF NEW YORK, N. Y., ASSIGNOR TO DWIGHT & LLOYD METAL- LURGICAL COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

APPARATUS FOR TREATING ORES TO SINTER THEM.

Original application flied December 23, 19 7, Serial No. 407,860.

14, 1912, Serial No. 883,780. Divided and this application filed To all whom it may concern:

Be it known that I, ARTHUR S. DWIGHT, a citizen of the United States, residing at New 'York, in the county of New York and State of New York, have invented oertain new and useful Improvements in Apparatus for Treating Ores to Sinter Them, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to the art of treating ores for the purpose of sintering them, especially such ores as contain or have mixed with them a readily combustible element or substance and are of such nature that combustion may be carried on therein after an initial igniting of the mass has been effected and which may, by reason of the said combustion, be sintered or have the articles thereof agglomerated into masses w ich are Well suited for subsequent treatment in blast furnaces. I may mention as one example of an ore such as the process and apparatus herein to be described are adapted to treat, a sulfid ore in which the combustible constituent, sulfur, is in sufficient quantity to permit the ore to be readily ignited and to burn if supplied with air or other supporter of combustion; and as another example of the material to be treated, I. may mention a mixture of pulverized or finely divided ore and pulverized coal or other form of carbon.

The invention relates particularly to the apparatus employed for effecting the initial ignition of the ore and maintaining the combustion therein until the entire mass is treated and sintered. The features which constitute the invention herein presented and claimed are capable of combination with any of numerous sorts of mechanisms for supporting and for carrying the ore during and after treatment, and in respect to said supporting and carrying mechanism the present invention is not limited.

For the purpose of illustrating how' the invention may be practically carried into effect, I have represented in the accompanying drawings. the mechanism for supplying and transporting the ore, and finally delivering it in sintered masses, which is shown, described and claimed in my application for patent filed December 23, 1907, original Serial Number 407 .860 on which issued Patent 1,027,110, dated May 21, 1912. This ap- Divided and application filed March May 8, 1912. Serial No. 685,888.

plication is a division of my application 683,760 filed March 14, 1912, which is itself a division of my aforesaid application filed December 23, 1907, No. 407,860, in which earlier divisional application are presented claims for the method or process of sintering ore herein described where the space immediately above the top surface of the layer or stratum of ore is enclosed and ignition of the ore is caused to take place within the said enclosed space.

In such drawings,

Figure 1 is a side elevation of an ore sintering machine in which the improvements herein presented and claimed are embodied.

Fig. 2 is a cross sectional view of one of the pallets, showing adjacent parts of the upper and lower air boxes.

Fig. 3 is a side elevation of one of the pallets or individual elements of the support and carrier for the ore, in the position occupied while the ore is being treated, and of parts of the apparatus immediately adjacent thereto.

Fig. 4 is a vertical transverse sectional view taken on the line IVIV of Fig. 1.

Fig. 5 is a central longitudinal section taken on the line V-V of Fig. 4.

Fig. 6 is a transverse sectional view of a sintering apparatus showing a different means for igniting the ore from what is shown in the views already described.

Fig. 7 is a cross sectional view through an apparatus like that represented in Fig. 1 showing the form of burner illustrated on Fig. 6 applied thereto.

In these drawings, A represents an air box suitably supported in a frame P. Its upper ends is open and with it is connected an olftaking duct T. Across the open end of this air box travel the pallets or ore receptacles D constituting the individual elements of an ore support and carrier. The pallets carry grates which are suitably supported therein and are of a construction to properly sustain the ore and at the same time permit relatively free passage of air and other gases through them. Each of these pallets, which may be described as an independent receptacle for receiving the ore and holding it quiescent while undergoing the sintering operations and then being inverted to discharge the sintered mass, is provided with wheels E, preferably four of them,which are attached to the pallet by suitable lugs carrying the axles e on which the wheels turn. Each pallet is formed with transverse end walls S connecting the side walls S, so that each grate is surrounded by four walls, forming an open box-like structure for the material bein treated. In the form of apparatus herein illustrated the pallets are arranged to be pushed across the open end of the box A where they are guided and directed by longitudinal tracks F with which the wheels engage.

A indicates an air box or hood supported above the air box A and connected by a pipe or trunk A with a fan A adapted to force air with the desired pressure into the hood A The lower end of the air box or hood A is open, and there is just sufficient space be tween the op osed open ends of the air boxes A, A for the pallets D to move between them. At the bottom edges of the hood or air box A are filler bars or joint bars B constituting wearing strips which are carefully planed, and with these engage the upper edges of the pallets, which are likewise carefully planed, as they pass alon the tracks F. The vertical edges of the pa lets, which abut as they come together end to end, are likewise finished so as to make air-tight vertical joints at the ends of the ore carriers where the individual elements thereof come together. At eachend of the air box or hood A is a cut-off plate or dead plate G the under surface of which is flat and coincident with the plane in which are situated the lower faces of the strips B Across these surfaces of the cut-off plates travel the upper surfaces of the pallets. with which they form air-tight joints at the respective ends of the hood or air-box A so that air leakage is prevented as the pallets either approach or leave the air box. i

At one end of the apparatus I have illustrated means for imparting motion to the ore support and carrier, these consisting of a pair of sprocket wheels, H, H. each of which is so designed that its teeth engage with the wheels E of the cars or pallets D. These wheels H serve to push the cars in an end to end series along the track P, and also to elevate them from the lower track F of the apparatus to working position. Curved guides F partially encircle the wheels H and assist in holding the pallets in engagement therewith.

At the end of the apparatus opposite the wheels H the tracks F are curved downwardly, as indicated at F, and opposite these tracks are concentrically arranged guide rails F. These operate to direct the pallets individually from the upper track F to the lower return track F K designates a hopper for feeding the ore to be treated to the carrier. The character of this feeder is not essential to the present invention. It is represented as being located just in advance of the cut-off plate G at the head end of the apparatus. It operates to deliver to each pallet or ore support D a thin bed of ore which is supported by the perforate grate O. The thickness of the bed of ore is such that the air which is supplied under pressure to the hood A readily passes therefrom transversely through the layer or bed of ore and into the air box A, whence it esca es, mingled with the products of combustlon and chemical reactions that are incident to the treatment which the ore is undergoing, through off-take duct T.

I have, in the ap lication of which this case is a division, fiilly described and explained that instead of employing air forcing apparatus to cause air currents to pass downwardly through the ore, use may be made of air suction apparatus for the same purpose.

In the sintering of ore according to the method of procedure herein described, it is common practice to ignite the ore at one of its surfaces, and after such ignition to complete the sintering by combustion carried on within the body of ore while the particles thereof are maintained in a state of quiescence and accelerated by transversely moving currents of air passing through the body of ore.

Accordin to my present invention the surface ignition of the ore is effected by the use of an igniter located within the hood A preferably near the end thereof adjacent to the feed hopper K. Any one of a number of forms of igniter may be employed.

. In Figs. 1, 4 and 5 ofthe drawings, I have illustrated an igniter adapted to sustain burning solid fuel and so arranged with reference to the surface of the ore as to deliver the hot products of combustion therefrom directly to a relatively broad surface of the ore. The igniting apparatus illustrated in these views is a brazier or small open furnace especially adapted for burning charcoal. coke or similar readily combustible solid fuel. In the bottom of this brazier is located a perforated screen L that supports the charge of fuel which it carries. The charcoal or other fuel within the holder L being ignited, the hot gases of combustion therefrom are carried downwardly by the general direction of air movement within the air box or bond A and are brought into contact with the ore. igniting it. As the charcoal or other fuel burns the ashes drop through the perforate screen and are carried off with the ore being treated.

In Figs. 6 and 7 I have illustrated a form of igniter that may be used in place of the igniter L and which is adapted for burning gasolene, naphtha, petroleum or other similar hydrocarbon or combustible fluid. It

consists of a pair of spray burners I, preferably located diametrically opposite each other above the e es of the bed of ore and so disposed that the flaming particles of burning fuel proceeding therefrom are applied to and caused to ass over and across the upper exposed sur ace of a relatively wide and extended area of the ore bed. The burners are supplied with fuel through a pipe I connected with any suitable source of supply and are provided with regulating va ves c.

In order to ermit the igniter to be inspected durin the operation of the machine, I form windows of mica in the sides of the air box, as indicated at a. The igniter may be lighted through a valved aperture in the wall of the air box or hood, such as indicated at a.

It will be apparent that in using either form of igniting apparatus herein illustrated and described, a wide area of the ore is at one and the same instant of time subjected to the igniting action of the hot gases of combustion or the flaming particles of matter in combustion, such igniting particles and products being, by the action of the currents of air which are caused to transversely pass through the ore mass, drawn into contact with the surface of the ore and somewhat into the body thereof. In these respects the igniters herein described and illustrated differ from igniting apparatus which I have shown in earlier patents of mine, for instance, in Patent 916,391 of March 23, 1909, wherein I illustrate an igniter consisting of a gas ipe extending transversely across the cd of ore and perforated or provided with tips arranged to direct small open jets of gas against the ore along a narrow transverse line of its surface. The igniting apparatus herein illustrated possesses the advantage of subjectin a comparatively large area of the exposed ody of ore simultaneously to ignition so that it is possible to insure a direct initial ignition of the entireisurface notwithstanding the fact that certain areas thereof may be difficult of ignition owing to a local deficiency in the combustible element of the mass, and which actually fail to become ignited when subjected to only a momentary or a very brief application of the igniting products.

A ain, by locatin the igniter within the hoof A, instead of having it in the open as represented in my aforesaid patent, I ard against the waste of heat incident to t e igniting flames or products of combustion being carried away from direct contact with the ore surface by currents of air sweeping transversely across the surface of the ore as is liable when the igniter is located in the open.

In using the apparatus shown the ore carrier is slowly moved and the pallets or individual elements thereof are filled from the hopper K. The air moving mechanism ceases air ts pass transversel" downward? through the ore upon the earner. Afterthe ore has been thorou hlyignited at the surface in the manner erein described, an active internal combustion is maintained within and throughout its mass, this latter stage of combustion taking place apart from the direct action of the igniter, this being seured by moving the pallets beyond the igniter after the surface ignition has been completed. The movements of the apparatus are so timed that a complete sintering of the entire mass of ore supported by any allet has taken place at about the time, or s ortly before, it arrives at the place where it leaves the air boxes A, A Shortly thereafter the pallet comes to the curved downwardly inclined portion F of the track, whereupon its motion is accelerated and it is inverted, causing a separation of the sintered mass from the pallet and the grate which it carries, and its discharge.

It will be seen, especially by reference to Figs. 2 and 3 of the drawings, that each holder for a mass of ore to be treated is boxlike in construction, being open at the top and having a perforated grate or support for the mass of ore material and with four gastight walls at the edges of the mass. The grate is preferably arranged so as to divide the box-like ore support into two chambers, in the upper one layer or stratum of ore, while the lower one serves as an air or gas chamber, having connection with the off-take duct, T, through the intermediate air box A. With an ore holder of this character and construction, the hood or air box A has temporary gastight connection, as has been explained. It is a matter of greater difliculty to remove the cakes or blocks of sintered ore from a holder having side walls around all its edges, such as described, than from an open ended sup port such as I have indicated in my aforesaid application of which this case is a division; ut this removal can be conveniently and ractically effected by tilting or inverting t e holder, as provided for in the apparatus herein illustrated, such tilting or inverting serving not only to separate the mass from the gas-tight confining walls of the holder, but also loosening-and separating it from the perforated rate, the perforations in which are well ceaned as the sintered mass falls away from the holder.

While, as stated, it is somewhat more diflicult to remove the sintered or agglomerated mass of material from a holder such as described, there are nevertheless advantages incident to entirely surrounding each holder with side or edge walls so that the cake block or mass of sintered or agglomerated material in each holder is maintained sepaof which is deposited the rate and distinct from each other mass of such material, for the reason that Whenthus separated the individual holders can be easily tilted or discharged; whereas, when the sintered mass extends continuously from one holder to the next throughout the series considerable force is required to break the 'sinter transversely whenever a holder is tilted for discharge. a

The apparatus herein illustrated and described is primarily devised for the purpose of sintering or agglomerating metalliferous materials which are originally in a pulverulent or fine condition and which have a combustible component. One of the elements of the apparatus has been termed the igniter and this, as its name suggests, is a device or means for merely setting fire to the combustible component of the mass, Which after ignition, and without reference to, or apart from, the igniter, is caused to be sintered or agglomerated by internal combustion carried on within the mass while the particles thereof are in such state of rest as to permit sintering or agglomerating action. The action of the i niter'is for a relatively brief period, consiifiaring the total period of time required to treat the mass to attain the result desired. Such igniter is to be distinguished from the fire chamber of .a reverberatory ore roasting apparatus or furnace, or from the burners of such a furnace, where the material to be treatedis subjected to the action of flame passing through the furnace throughout the entire period of treatment and where the roasting, calcining or other desired effect upon the material is directly and primarily produced by the action of such flame. 1

Again, another element of the apparatus is the air box or hood that covers the material during a part of the time while in the carriers, and in which the igniter is located. It is to be understood that this element of the apparatus and the carriers or holders for the material being treated are so constructed and related, with reference to each other, that they are easily separated in order that the carriers or holders for the material may betilted for the purpose of discharging their contents.

I do not in this application claim the mechanism for supporting and conveying the ore and for causing air currents to pass through the ore while being supported and conveyed which is illustrated and described in this application, as such apparatus is claimed in my aforesaid Patent 1,027,110. The said mechanism in so far as it is a conveying apparatus capable of use for other purposes than in the roasting, sintering and similar treatment of ore, is also claimed by me in my Patent 1,027,111 of Ma 21, 1912.

h isither do I herein ciaim the specific form of igniting mechanism illustrated in Figs. 6 and 7 of this case, as this is made the subject of an application which I have made as a division of my aforesaid application Serial Number 407,860, and bearing Serial Number 685,909, filed March 25, 1912; nor the process of sintering a thin bed of ore by igniting a wide area of the surface thereof at one and the same instant of time by a broad mass of flaming particles such as is produced by the igniting means illustrated in Figs. 6 and 7 hereof, and then sintering or agglomerating the mass, as this subject matter is presented and claimed by me in my application 695,882, filed May 8, 1912, which is also a division of my appli' cation 407,860.

Nor do I herein claim the specific form of igniter illustrated in detail in Figs. 4 and 5, as this forms the subject of another application which I have made as a division of my application Serial Number 407,860, bearing Serial No. 685,910, filed March 25, 1912; nor do I herein claim the process or method of sintering or agglomeratin metalliferous substances which are initial y in a fine condition, which consists in igniting the same by applying to a broad area of, the upper surface thereof a laterally defined body of flame or other igniting material and then sintering by internal combustion carried on within and through the mass of material, as this subject matter is presented and claimed by me in an application filed May 20, 1912, Serial No. 698,467, also as a division of my aforesaid application 407,860.

What I claim is 1. In an apparatus foragglomerating or sintering ore, a perforate support for a thin bed of ore, a hood for covering the ore while upon the support, means for causing currents of air or other supporter of combustion to pass through the ore while covered by the hood, and an igniter arranged Within the hood for setting fire to the ore at its surface.

2. In an apparatus for agglomerating or sintering ore, a perforate support for a thin bed of ore, a hood covering the ore while upon the support, an air box arranged below the said support and with which is connected an off-take duct, means for causing a up porter of combustion to enter the hood and pass thence through the ore and into the air box below the ore support, and an igniter for the ore located within the hood.

3. In an apparatus for agglomerating or sintering ore, the combination of a rforate support for a thin bed of ore, a ood for covering the ore while u on the support, an

igniter located within t e hood for setting fire to the ore at its surface, comprising a burner that supplies hot products of combustion for igniting the ore and means for supplying the hood with alr to maintain ofi the said thin f combustion at the said igniter and cause the products of said combustion to impinge upon the surface of the ore.

In an apparatus for agglomerating or sintering ore, the combination of a perforate support for the ore, a hood for covering the ore while upon the support, an ignite! located within the hood and arranged to direct hot products of combustion into intimate contact with a broad area of the surface of the ore, and means for causing currents of a gaseous supporter of combustion to pass through the ore while covered by the hood.

5. In an apparatus for agglomerating or sintering ore, a perforate support for a thin bed of ore, a hood for covering the ore while upon the support, an igniter arranged Within the hood for setting fire to the ore at its surface, and means for causing combustion of the ore to be continued apart from the igniter after the said surface ignition thereof.

6. In an apparatus for agglomerating or sintering em, aperforate support for a thin bed of ore, a hood for covering the ore while upon the support, an igniter arranged Within the hood for setting fire to the ore at its surface, means for causing combustion of the ore to be continued apart from the i niter after the said surface ignition thereo and means for inverting the said ore sup ort to cause it to discharge the ore mass it contains after it has become thoroughly sintered.

In an apparatus for forming relatively thin cakes of agglomerated or sintered ore from a mass initially containing a metalbearing material'in pulverized form and a combustible ingredient, the combination of an open top movable holder adapted to have disposed therein a relativel thin layer of the said mass and having Wall s surrounding the said layer and a perforate bottom on which it rests, an air-supplying mechanism, a hood having an open bottom located above the open top of the said holder, igniting means within the hood arranged to set fire to the combustible ingredients at the surface mass, means for moving the holder beyond the range of i ition of the igniting means, and means or tilting the hol er to remove the sinter cake formed therein from the walls which surround it.

In an apparatus for formin relatively cakes of agglomerated or slntered ore rom a mass initially containing a metalbearing material in pulverized form and also a combustible ingredient, the combination of a holder adapted to have disposed therein a relatively thin layer of the-said mam and having a perforate bottom on which the mass rests, and walls wrreimding the sides thereof, means for igniting the combustible ingredient of the mass at the surface of the said layer, means for causing combustionsupporting gas to pass throu h the said layer, and means for tilting the older to remove the sinter cake from the space surrounded by the aforesaid walls and cleaning out the perforations in the said bottom on which it rested.

9. In an apparatus for forming relatively thin cakes of agglomerated or sintered ore from a mass initially containing a metal bearin material in pulverized form and also a com ustible ingredient, the combination of a holder arranged to be tilted and adapted to have disposed therein a' relatively thin layer of the said mass, and having a perforated bottom, and walls surrounding the said layer on all sides, means for igniting the combustible ingredient of the said mam at the surface of the layer, and means for carsing combustion-supporting gas to pass through the layer afteri nition to gradually form-a cake of sinter, which cake is removable from the holder when it is tilted.

In an apparatus for forming relatively thin cakes of ag lomerated or sintered ore from a mass initial y containing a metalbearing material in pulverized form and also a combustible ingredient, the combination of a holder for a relatively thin layer of the said mass having a perforated bottom, arranged between an up r ore chamber and a lower gas chamber t ereof, a superjacent hood located over a rtion of the ore mass being treated, means in the hood for causing ignition of the combustible element of the mass at the upper surface of the layer there of, means for causing combustion-supporting gas to move downwardly through the hood, through the region of ignition, and then through the ore layer, a duct below the ore holder ada ted to communicate with the gas chamber t ereof for carrying away the air and gases which pass throu h the ore mass in the holder and means 5)! moving the holder relative to the igniting means whereb the ore therein is first brought into proximity to the igniting means and is afterwards moved therefrom to rmit the finishing of the sintering operatlon apart from the igniting means.

In an apparatus for forming relatively thin cakes of agglomerated or sintered ore to a mass initially containing a metalbearin material in pulverized form and also a com ustible in redient, the combination of a movable hofiler for a relativel thin layer of the said mass bottom, arranged between an u per ore chamber and a lower gas chamber t ereof, a superjacent hood adapted to temporarily cover the ore layer, means in the hood for causing ignition of the combustible element of the mass at the upper surface of the layer thereof, means for causing combustionsupporting gas move downwardly through having a per orated the hood, through the region of ignitior and then through the ore layer, a duet below the ore holder adapted to communicate with the gas chamber thereof for ('arrying away the air and gases whieh pass through the ore mass in the holder, means for moving the holder to bring the ore curried thereby helow the igniting means and then to carry it beyond the infiuener thereof and means for tilting the holder to discharge the sintered 10 ore therefrom.

In testimony whereof I afiix my signature, in presenve of two witnesses.

ARTHUR S. DWIGHT. W itnesses Romurr TANBY, Louis H. HYDE.

DISCLAIMER 1,433,352.-Arthur S. Dwight, New York, N. Y. Arrana'ros ron Tnm'rmo Onns 'ro Sm'rnn THEM. Patent dated October 24, 1922. Disclaim' er filed October 21, 1931, by the assignee, Dung M (1: Lloyd Simering Company, Inc.

Hereby enters this disclaimer to claims 1, 3, 4, 5, 8 and 9 of said Letters Patent, which are in the following words, to-wit:

"1. In an apparatus for agglomerating or sintering ore, a perforate support for a thin bed oi.ore, a hood for cover-mg the ore while upon the support, means for causing currents of air or other supporter oi combustion to pass thro h the ore while cove byrphe hood, and an igniter arranged within the hood for setting fire to the ore at its s ace."

"3. In an apparatus for agglomerating or sintering ore, the combination of a perforate support for a thin bed of ore, a hood for covering the ore while upon the support, an iiniter located within the hood for setting fire to the ore at its surface, comprising a urner that sugplies hot products of combustion for igniting the ore, and means for supplying the end with air to maintain combustion at the said igniter and cause the pro nets of said combustion to impinge upon the surface of theore.

4. In an apparatus for agglomerating or sintering ore, the combination of a perforate support for the ore, a hood for covering the ore while upon the support, an igniter located within the hood and arranged to direct hot products of combustion into intimate contact with a broad area of the surface of the ore, and means for causirrgi gurrilalntisgda gaseous supporter of combustion to pass through the ore while cove "5. In an, apparatus for agglomerating or sintering ore, a perforate support for a thin bed of ore, a hood for covering the ore while upon the sugport, an igniter arranged within the hood for setting fire to the ore at its surface, an means for causing combllllstlolfl of the ore to be continued apart from the igmter after the said surface ignition t ereo "8. In an apparatus for forming relatively thin cakes of agglomerated or sintered ore from a mass initially containing a metal-bearing material in pulverized form and also a combuetible'inmdient, the combination of a holder adapted to have disposed therein a relatively t layer of the said mass and having a perforate bottom on which the mass rests, and walls surrounding the sides thereof, means for the combustible ingredient of the mass at the surface of the said la er, means for causing combustion-supporting gas to pass through the said layer an means for tilting the holder to remove the sinter cake from the space surrounded by the aforesaid walls and cleanin out the perforations in the said bottom on which it rested.

-9. u an apparatus for forming relatively thin cakes of agglomerated or sintered ore from a mass initially containing a metal-bearing material in pulverized form and also a combustible ingredient, the combination of a holder to be tilted and ada ted to have disposed therein a relatively thin layer of the sai mass, and having a orated bottom, and walls surrounding the said layer on all sides, means for igniting the combustible ingredient of the said mass at the surface of the layer, and means for causing combustion-supporting gas to pass throu h the layer after 'tion to graduall form a cake of sinter, which cake is removab e from the holder w en it is tilted. nder claim 6, no claim is made except to an apparatus having a movable support ior the ore and means for moving said support beyond the range of ignition of the igmter.

[Oficial Gazette, November 17, 1981.] 

